One of the most well known global navigation satellite systems (GNSS's) is the Global Positioning System (GPS). Other GNSS include, for example, the GLObal NAvigation Satellite System (GLONASS) and the European Galileo positioning system (Galileo). A GNSS may be used in conjunction with a user device (e.g., a standalone GNSS device or a GNSS-enabled mobile communication device) to achieve one of a plurality of functions. For example, such a device may assist a user in navigating roads that the user may not be familiar with to reach the user's destination. Upon user entry of a desired destination, the device may use information received from one or more GNSSs among other information received and/or stored in the device to determine the exact location of the device and may further determine a route that will assist the user to reach the desired destination. In another example, the GNSS may be used in conjunction with the user device to determine a user's location or to provide the user with a map surrounding the user's location.
While traditional stand-alone navigation devices still exist, technology now allows user navigation devices to be a part of a mobile communication device such as a cellular phone or a personal data assistant (PDA). Such navigation devices may receive assistance data from a server, in addition to signals from the various satellites of the various GNSSs. Assistance data may allow the user navigation device to gain certain advantages, such as detecting GNSS signals quicker than without the assistance data and detecting weaker signals. While mere sending of assistance data from a server to a user navigation device is already possible, current methods are not optimal.